George gilmotjr



N. PETERS, FHOTCM THOGRAPHER wAsHlN r re UNITED STATES PATENT FFICE.

GEORGE GILMOUR, OF CHELSEA, MASSACHUSETTS, ASSIGNOR TO G. GILMOUR AND H.R. GLINKARD.

SECOND-ANCHOR SHACKLE.

Specification of Letters Patent No. 16,821, dated March 10, 1857.

To all @071.40m t may concern:

Be it known that I, GEORGE GILMOUR, of Chelsea, in the county of Suffolkand State of Massachusetts, have invented a new and useful contrivanceor mechanism for shackling or attaching` another` anchor to the chain ofan anchor to which a vessel may be riding, my said invention beingtermed by me a second-anchor shackle, and I do hereby declare that thesame is fully described and represented in the following specificationand the accompanying drawings, of which,-

Figure 1 denotes a top view of it. Fig. 2, a central, vertical, andlongitudinal section of it. Fig. 3, a horizontal section taken throughits spring iiy or pawl. Fig. 4, a longitudinal section taken through oneof its spring latches.

In the drawings A denotes a. bifurcated block or frame, having arrangednear the extremities of the prongs e, e, of its fork, a roller B, suchbeing as seen in the drawings. Combined with the opening C, of saidframe, or applied to the rear part of it, is a forked pawl, D, whichturns freely on a pin E one hundred and eighty degrees, or from theroller B over and toward one or more lever catches or latches F, F,arranged in the frame A, as shown in Figs. l and 4. A spring G, shouldbe so applied to the pawl D, and the frame A, as not only to allow saidpawl to be revolved from the roller B to the catches F, F, but to causethe said pawl when the catches are unlatched to be sprung smartly towardor against the roller or a chain while passing through the opening C.The spring catch or catches are forced toward the pawl, or maintained inengagement with it, by the action of one or more springs suitablyapplied to them and the frame A, such being shown at H, in Fig. 4. Awire I, jointed to the lever catch and extending and sliding freelythrough the frame A, in manner as shown in Fig. 2, enables the catchesto be so operated or moved as to disengage them from the pawl D, asoccasion may require. The block or frame A, should be constructed in aproper manner to enable a chain or anchor to be attached to the front orprojecting part K, and in order to enable the pawl and roller to operatetogether to advantage I prefer to make the roller with teeth orprojections as seen at a, a, and also with a groove b extending aroundit, the whole being as shown in the drawings.

In using an apparatus constructed substantially in the above describedmanner it is to be attached to an anchor which it may be desirable tosend down upon a chain of a vessel or ship while riding at anchor, theobject being to apply a second anchor to said chain under circumstancesthat may require the same. The secondary anchor may be attached to theblock A by a short chain.

In carrying on the operation of applying said apparatus to the vesselsriding chain we first turn over the pawl and latch it by its catches.Next the pin c, by which the roller D is kept in place in the frame A,should be drawn out of the roller and frame so as to allow the frame A,to be passed up underneath the chain, and receive said chain into theopening C. This done, the roller and pin should be put back in placeagain. A line or rope of small diameter and of sufiicient length shouldbe attached to the wire I. The apparatus is then ready for the secondanchor to be dropped from the cat head, or part of the vessel from whichit may be suspended. After the anchor has been cast oftl from the cathead, its weight acting on the shackle will draw said shackle down uponthe riding chain of the main anchor until the secondary anchor may reachits destination in the bottom of the sea, which having taken place theline attached to the wire I should be pulled so as to unlatch thecatches and permit the pawl to be thrown over so as to act between thelinks of the riding chain and clutch the secondary anchor to the saidriding chain of the main anchor. At the same time that the shackle isbeing taken down by the secondary anchor such shackle if desirable, maycarry down with it a chain, cable, or messenger attached to it, suchbeing also connected to the vessel. Furthermore in case a chain shouldpa-rt at or near the main anchor or at any distance above the same, thatApartfef its chain which hangs from the vessel may have by my shackle orinvention, an anchor attached to its lower part, as by knowing about thelength of said chain or part depending from the vessel, and having thetripping line suitably marked we may stop the anchor shackle at suchpart of the chain as may be desirable.

My invent-ion is one of great value and importance as by means of it avessel may be often saved from being wrecked or driven on shore.

I am aware that a patent has been applied for by IVm. J. Stetson on .ahoisting block made so as to contain a holding pawl and a trippinglever. In this block the purpose of the tripping lever is to force thepawl out of engagement with the chain extending around the sheave of theblock and in order that such chain may run freely over the sheave. Thishoisting block, however, has little similarity to my anchor shackle, norcould it be employed for the same purpose, as its peculiar constructionwould prevent it from being so used. Although in common with such blockI employ a roller and pawl, yet I use no tripping lever to operateagainst the pawl in such manner as to elevate it, out of engagement withthe chain. The latching apparatus or trigger of my anchor shackleoperates to hold the pawl back against the reacting power of the springof said pawl.

Vhen the cord of the latching apparatus is pulled backward, the force oftract-ion operates to set the pawl free so as to enable its spring tothrow it over and into engagement with the chain so as to confine theblock thereto. Besides this, the latching apparatus or trigger leversand the roller of my said anchor shackle are arranged at opposite endsof the frame A, and have the pawl disposed and hinged between them, insuch manner that it may turn or be turned over through a semicircle andfrom the roller to the latches and vice versa, the same causing the pawlto be entirely out of the way of the chain, while the anchor shackle maybe running down upon it. Furthermore the paWl is formed forked or with arecess by which it is enabled to straddle a link of the chain, andthereby hold the chain to much better advantage than it would were itmade so as to extend only against the front of the link and between thetwo adjacent connecting links and not straddle the middle link.

I do not claim a hoisting block made with a pawl and tripping lever soapplied to the pawl as to enable a person to elevate the latter out ofenga-gement with a chain when passing around the sheave of the block,but

What I claim isl. My new or` improved anchor shackle as made with aspring pawl, D, and trigger or latching apparatus FF, etc.,) arrangedwith reference to the roller, B, and made to operate substantially asdescribed.

2. I also claim making the pawl forked or with a recess so as to enableit to st-raddle the chain as described.

In testimony whereof I have hereunto set my signature.

GEO. GILMOUR.

Witnesses:

R. H. EDDY, F. P. HALE, Jr.

